Kim Seung-youn, the CEO of the Hanwha group in South Korea, has been sentenced to four years in prison and fined 5.1 billion won ($4.5 million). The jail time marks an unusual departure for the Korean judiciary who typically issue suspended sentences when prominent business bosses are found guilty.

Hanwha is the tenth largest “chaebol” or business conglomerate in South Korea. Started by Kim Chong-Hee as Korea Explosives Inc. in 1952, it now has an annual revenue of $30 billion and interests as diverse as dairy farming, finance and petrochemicals.

Kim Seung-youn, the son of the founder, has been in trouble with the law several times. In 1993 he was found guilty of smuggling cash to buy a large mansion in Los Angeles and then in 2004 he was found guilty of bribing a politician. In 2007, he was given a suspended sentence for assaulting workers with a steel pipe after his son got in a fight.

This time Kim has been accused of buying and selling shares in employees names to avoid taxes, bailing out his brother’s failing business and forcing his affiliates to sell shares in an oil company to his sister at below market prices.

"As a controlling shareholder of Hanwha Group, the defendant is passing on his responsibility to working-level officials and he has not shown remorse," said Seo Kyung-hwan, one of the three judges on the panel that decided the case. “Considering this, he needs to be strictly punished.”

Most chaebol got their start after the end of the Second World War when the government of Syngman Rhee encouraged entrepreneurs to rebuild the country. During the administration of General Park Chung Hee in the 1960s, the favored chaebol were given easy access to loans, foreign technology and large government contracts in order to rapidly industrialize the country. Today these elite companies – some of which have become global players like Hyundai, LG and Samsung – control much of the South Korean economy.

A few brave whistleblowers have risked their careers to speak out against the chaebol. "Our society is so corrupt, and people are blindfolded because everyone is living well and people are greedy,” says Kim Yong-chul, a Samsung whistleblower. “I am not a revolutionary, an ideologue or a revenge. But I am against business as usual.”

Kim wrote a book about his experiences: "Thinking of Samsung" ("Samsungul Sanggak Handa"). The book was never reviewed by the South Korean media and he has been ostracized by the business establishment. “Isn’t this a comedy?” Kim told the New York Times. “I am challenging them to slap my face, to file a libel suit against me, but they don’t. They treat me like a nut case, an invisible man, although I am shouting about the biggest crime in the history of the nation."